South Africa's second-largest city and its surrounding areas received between 2 millimeters and 10 millimeters of rainfall Friday night, according to the Cape Town Weather Office. The city can expect 2 millimeters to 8 millimeters of rainfall Monday evening and into Tuesday morning -- less than an inch -- with no further rain expected later in the week.

Despite the paucity, the precipitation was a welcome sight for residents who haven't seen rain since January 22, and they collected water in buckets and tanks, with plans to use it for everything from washing clothes and dishes to flushing toilets.

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But it is unlikely to make a significant impact on the city's largest reservoir, Theewaterskloof Dam, which satellite images show is at dangerously low levels.

'You feel guilty flushing toilets'

Since February 1, residents have seen their water usage downsized from 87 to 50 liters a day -- or a little over 13 gallons.

The city is also rushing to upgrade its water systems and is building desalination, aquifer and water-recycling projects to help stretch the current supply.

"The water restrictions have been crazy, " 32-year-old Cape Town resident, Wayne Ronne said. "We are not allowed to have baths. We are allowed to have showers, though not every day. We have stocked up [on] bottled water, hand sanitizers and wet wipes. You literally feel guilty when flushing."

Ronne said when Friday's rain started, he and his brother took out buckets to collect water from gutters. "This would be used for the washing machine, dishes, etc," he said.

Another Cape Town resident, 30-year-old Jennifer Stock, said no drop of precious water is wasted in her home. "We shower over buckets, and then use that water elsewhere in the house or garden," she said.

"We have to think about everything we do, prioritize what we will use our water for -- do I want a cup of tea or to be able to keep a small plant alive that will help the bees and birds survive?"

She added, "You can't have a nice long shower after a hard day's work."

People stockpiling water

People queue to collect water from a natural spring outlet in the South African Breweries in Cape Town.

Amid the crisis, the city is suffering a shortage of bottled water. The stores that do have water sell out fast and are unable to replenish their stock for days.

Those who can afford bottled water are queuing up at stores before they open. At one local chain grocery store, video shows shoppers swarming pallets of bottled water, clearing them in just minutes.

"The price of bottled water is going up because people are going crazy buying water, so supermarkets are running low on supplies," said 32-year-old Cape Town resident Shantalie Hewavisenti.

"It's also a big worry for people in the township community who don't have the same means as the middle class people," she said.

What happens next?

Should the government declare "Day Zero" has arrived, faucets will cease to deliver water until the skies open and more rain falls.

On this day, residents will be further rationed to just 25 liters (6.6 gallons), which they will be able to collect only from one of 200 stations. To put that into perspective, each collection point will have to accommodate the water needs of 20,000 residents.

Key institutions -- such as schools and hospitals -- are expected to continue receiving water after Day Zero, according to officials, who have said contingency plans have been made.